Starch hydrolyzate extended hydrolyzed vinyl ester polymeric systems



United States Patent 3,488,724 S'IARCH HYDROLYZATE EXTENDED HYDRO- LYZED VINYL ESTER POLYMERIC SYSTEMS Donald D. Donermeyer, Springfield, and Robert A. Isaksen, East Longmeadow, Mass., assignors to Monsanto Company, St. Louis, Mo., a corporation of Delaware No Drawing. Filed Mar. 3, 1967, Ser. No. 620,224

Int. Cl. C08b 25/02; C08f 25/00, 3/54 US. Cl. 260-17.4 9 Claims ABSTRACT OF THE DISCLOSURE The application describes hydroxy-containing polymer systems which are extended up to levels of about 75 Weight percent with non-crystalline starch hydrolyzates having a dextrose equivalent of from about 13 to about 38. The extended resin systems exhibit compatibiliy both in solution and in solid form and find utility as film formers, adhesives, binders and sizing compositions.

This invention relates to hydroxy-containing polymers extended with particular starch hydrolyzates.

Polyvinyl alcohol and other high molecular weight hydroxy-containing polymers have been modified with various additives such as clay, boric acid, metal salts, starch, urea, glycerine, and sugars in an effort to improve the properties of and increase the economic performance of polymers. However, in many cases, either the expense of the additives has prohibited their use commercially, or the additives have enhanced one property of the polymer only at the sacrifice of another property. Also, the quantity of such additives or level of extension of such polymers heretofore employed has been limited, i.e., less than about 25 Weight percent because of incompatibility. It would be of course desirable to extend hydroxy-containing polymers to higher levels for economic reasons.

In many applications where hydroxy-containing polymers are utilized initially as as solution and then dried to a solid, compatibility of the additive with the polymer presents a major problem. Many additives, such as starch and low molecular Weight saccharides, are dissolvable or dispersible in hot Water but exhibit retrogradation with crystallization upon cooling. Thus, when the additives are used as high level extenders for hydroxy-containing polymers, the retrogradation of the additives upon cooling or during film formation yields two-phase films which have poor mechanical and physical properties.

Accordingly, typical objects of this invention are to provide: (1) novel extended hydroxy-containing polymer systems: (2) hydroxy-containing polymer systems containing more than 25 Weight percent of an extender and which exhibit compatibility both in solution and in solid forms; and (3) a hydroxy-containing polymer system which possesses a combination of numerous specific desirable properties.

Other objects, aspects and advantages of this invention will become apparent to those skilled in the art upon further study of this disclosure and the appended claims.

In accordance with the present invention, the above objects are realized through the provision of a composition comprising a water-soluble hydroxy-containing polymer and up to about 75% by weight of a non-crystalline hydrolyzate of starch having a dextrose equivalent (hereinafter defined) of from about 13 to about 38, with or Without other extenders or additives.

The present invention is based upon the discovery that particular hydrolyzates of starch, besides improving various properties of high molecular Weight hydroxy-containing polymers, remain compatible with such polymers both in solution and in solid forms in a quantity of up to about 3 parts of hydrolyzate' to 1 part of polymer.

The starch hydrolyzates applicable to this invention are non-crystalline and can be formed from any starch. The corn starch derivatives are presently preferred because of their commercial availability. The hydrolysis of corn starch to convert starch to dextrose is well known and is carried out by use of acid alone or by use of acid initially followed by enzyme hydrolysis. However, the conversion reaction may be regulated to produce intermediate hydrolyzates containing various amounts of intermediate products in the chemical path from starch to dextrose. The characteristics ofa product as a hydrolyzate is expressed by a DB number which is the ratio of dextrose equivalent, or in other words, of reducing sugars, to the total dry substance of the hydrolyzate. Completely hydrolyzed corn starch is com sugar or dextrose which has a 100 DE. The commercial intermediate hydrolyzates of corn starch are termed 1 dextrins 13 D.E.), maltodextrins (13 to 28 DE), and corn syrups (28 and higher D.E.). The corn syrups are further classed by degree of conversion, i.e. low (28 to 38 D.E.), regular (38 to 48 D.E.), intermediate (48 to 58 D.E.), high (58 to 68 D.E.) and extra high (68 and higher D.E.). Relative to colloidal starch, the hydrolyzates are non-colloidal compounds of small molecular size and are of such character that they may be dried to a powder. The starch hydrolyzates found operable and compatible with bydroxy-containing polymers in accordance with this invention are those termed malto-dextrins and low conversion corn syrups, i.e. having a DB ranging from about 13 to about 38. w

The hydroxy-containing polymers applicable to this invention include the polymeric materials having a viscosity determined from a 4% aqueous solution at 20 C. up to about 200 centipoises and containing a plurality of recurring hydroxy groups either in the form of the alcohol or partially esterified alcohol.

More specifically, one group of hydroxy-containing polymers suitable for use in this invention are the (A) Water soluble homopolymers of vinyl esters which are from to and preferably from 87 to 99% hydrolyzed; ('B) water soluble hydrolyzed copolymers of at least 50 weight percent of a vinyl ester and up to 50 weight percent of an e'thylenically unsaturated material copolymerizable therewith, such as ethylene, propylene, acrylates, vinyl chloride, maleates, fumarates, and the like or mixtures thereof; and (C) physical blends of (A) and (B). Examples of *suitable hydroxy-containing polymers are polyvinyl alcohol, partially hydrolyzed polyvinyl acetate, partially hydrolyzed polyvinyl propionate, partially hydrolyzed polyvinyl butyrate, partially hydrolyzed polyvinyl stearate, partially hydrolyzed polyvinyl trifluoroacetate, and the like; partially hydrolyzed copolymers of vinyl acetate with ethylene, vinyl chloride, or acrylonitrile, and the like. Polyvinyl alcohol is the presently preferred polymer.

Further, in accordance with the present invention, other extenders and plasticizers for hydroxy-containing polymers, such as boric acid, urea, glycerine, and the like, may be employed in combination with the particular starch hydrolyzates set forth above as extenders for such polymers to advantage. Although such other extenders are not compatible alone with such polymers at extension levers above about 25 weight percent, it has presently been discovered that they do achieve compatibility with such polymers in the presence of particular starch by drolyzates at high levels of total extension of the poly- Com Syrups and Sugars, 3rd edition, 1965, Corn Industries Research Foundation. Inc., page 15.

mers. When a combination of extenders is employed, the

particular 'starch hydrolyzates should comprise at least Films of polyvinyl alcohol employing different extenders at various levels of extension are prepared by casting aqueous solution admixtures of the materials onto a glass plate, the surface of which is coated with polyester film (polyethylene terephthalate). The films are dried at elevated temperatures (about 50 C.) to drive off water. The films are removed from the casting plate, subjected to about a 76% relative humidity and tested for tensile and elongation properties. The polymer, extender, ratio of extender to polymer and the test data for each film is given in Table 1.

The solutions are prepared by slurrying the polyvinyl alcohol and particular hydrolyzate in water and then heating the slurry until a solution is formed, The solutions using dextrin and starch are prepared by slurrying the extender in cold Water and then cooking the slurry at 190 F.210 F. until a constant viscosity is achieved. The latter two solutions are cast onto pro-heated glass plates to avoid retrogradation of the extender.

TABLE 1 Coinpat ibility 3 of ex- Polymer Extender tender weight, weight, Tensile, Elongation, Toughwith percent percent lbs/sq. in. percent ness 2 polymer 90 4 10 4, 960 300 15,000 No. 80 l 20 3, 720 200 7, 500 No. 70 4 30 3, 900 160 6, 400 No. 90 5 l 4, 950 370 18,300 No. 80 20 4, 660 340 15, 600 No. 70 5 30 4, 110 390 15, 000 No. 90 a 5, 030 300 15, 200 No. 80 5 4, 030 270 11, 000 No. 70 l! 2, 450 160 4, 000 No. 90 7 10 5, 300 430 22, 600 Yes. 80 7 20 4, 400 340 14, 900 Yes 70 7 30 8, 640 350 12, 800 Yes. 50 7 50 2, 800 660 18, 500 Yes. 7 60 2, 020 580 11, 700 Yes 30 7 70 1, 220 630 7, 700 Yes. 20 80 400 390 1, 600 N o. 5 50 1, 870 630 11, 800 Yes '40 9 1, 310 600 7, 900 Yes 30 5 720 520 3, 700 No. 50 7 50 1, 310 570 7, 500 Yes 30 9 70 800 550 4, 400 No. 20 4, 000 450 18, 000 Yes 60 40 1, 800 540 9, 700 No. 4, 500 440 18, 000

90 4 10 1, 680 350 5, 900 No. 80 4 20 1, 270 320 4, 200 No. 90 5 10 2, .500 350 8,800 No. 80 5 20 3, 150 250 8, 000 No. 70 5 30 2, 750 260 7, 000 N0. 90 5 10 2, 750 280 7, 600 N o. 80 5 20 3, 500 230 8, 000 No. 70 6 30 2, 150 2, 700 No. 90 7 l0 3, 540 380 18, 400 Yes 80 7 20 3, 200 380 12, 000 Yes 70 7 30 3, 050 480 14, 600 Yes 50 7 50 2, 770 450 12, 500 Yes 50 8 50 2, 400 500 12, 000 Yes 50 7 50 1, 800 600 10, 800 Yes 90 11 10 2, 060 570 11, 700 No. 50 7 45+ 5 2, 600 630 16, 300 Yes "50 7 40+ 10 2, 520 11,200 Yes 50 7 35+ 15 1, 660 480 8, 000 Yes 40 7 50+ 10 1, 470 470 7, 000 Yes 60 7 30+ 10 2, 430 640 15, 500 Yes 50 7 35+ 15 1, 730 610 10, 500 Yes 90 13 10 1, 700 600 10, 200 No.

The polymer employed in test films 1 through 24 is a 97.999% hydrolyzed polyviny alcohol having a viscosity of 45-55 centipoises determined at 20 C. from a 4% aqueous solution and is marketed. by Monsanto Company as GELVATOL 3-90. The polymer employed in test films 25 through 47 is an 88-89% hydrolyzed polyvinyl alcohol having a viscosity of 35-45 cerrt-ipoises determined at 20 C. from a 4% aqueous solution and is maror shows the presence of crystallytes, or the extender exudes to the surface; or the properties of the systems are interior.

4 A com dextrine having a D.E. of 8-8.5 and marketed by American Maize Products Co. as .Amaizo 1413 Dextri e.

5 A white dextrine hav Co. as Amaizo 1415 De trine.

6 An ethoxylated po ato starch marketed by Morningstar Paisley Co. as Starfilm 3-95.

7 A corn starch hydrolyzate having a D.E. of 18 and marketed by American Maize Products Co. as Frodex 15.

8 A corn starch hydr'oly ucts Co. as Frodex 24CN..

9 A corn starch hydrolyzate havin Dri Sweet.

' Sucrose. Lactose.

12 Glycerine.

1 Urea,

ing an 85-92% cold water solubility and 200-400 cps. viscosity determined from a 50%.s'olut1on at /75 F. and marketed by American Maize Products zate having a D.E. of 24 and marketed by American Maize Prodg a 13.15. of 36 and marketed by The Hubinger Co. as

Although the novel composition provided by this invention has been described in the preceding specific examples in regard to the formation of the films, the composition is equally useful as adhesives particularly of the types known as corrugated and remoistenable, as binders in joint cement, as particle binders for temporary sands, forms or molds, and as a sizing composition for papers, textiles, yarns and filaments.

The novel composition of this invention may also be utilized to advantage with the presence of other known extenders or plasticizers. Typical examples of such are, but not limited to, urea, glycerine, metal salts such as magnesium chloride, magnesium sulfate, glycols, trimethylol propane, 1,3-butanediol, and the like.

One area in which the extended polymeric systems of this invention produce particularly superior resultsis in the sizing of synthetic and natural textile yarns and filaments, In preparing aqueous solution for use in sizing textile yarns, the vinyl ester homopolymers employed are at least 85% hydrolyzed having a viscosity determined from a 4% aqueous solution at 20 C. of from about 15 to about 200 centipoises, and the vinyl ester copolymers and physical blends of homopolymer and copolymer are sufiiciently hydrolyzed to provide water-soluble systems. The exact degree of hydrolysis necessary in the vinyl ester to produce water-solubility will vary with the amount and solubility characteristics of the other polymeric constituent present. The aqueous sizing solution is applied to the textile yarn in amounts of 1-20 weight percentbased upon the weight of the textile yarn. Textile yarns sized with the polymeric complexes of this invention exhibit excellent slasher performance and weaving efliciency with a minimum of warp stops, permitting efficient removal of the sized yarn from the slasher without yarn breakage.

Various modifications will be apparent to those skilled in the art from the preceding disclosure which may be made in or to the composition disclosed and which will not depart from the spirit and scope thereof.

What is claimed is:

1. A composition comprising:

(A) from about 25 to about 75 weight percent of a first component comprising a water-soluble hydrolyzed vinyl ester polymer; and correspondingly (B) from about 75 to about 25 weight percent of a second component comprising a non-crystalline starch hydrolyzate having a dextrose equivalent of from about 13 to about 38; said weight percentages being based on the total weight of the composition.

2. The composition of claim 1 further being in an aqueous solution.

3. The composition of claim 1 wherein said polymer has a viscosity up to about 200 centipoises determined at 20 C. from a 4% aqueous solution of said polymer.

4. The composition of claim 3 wherein said polymer has a viscosity of from about 15 to about 200 centipoises.

5. The composition of claim 3 wherein said polymer is a vinyl ester polymer which is 85-l00% hydrolyzed.

6. The composition of claim 5 wherein said polymer is a vinyl ester homopolymer which is 87-99% hydrolyzed.

7. The composition of claim 6 wherein said homopolymer is polyvinyl alcohol.

8. The composition of claim 1 further containing an additional extender in a quantity up to about by weight of said starch hydrolyzate, provided however that the total quantity of starch hydrolyzate and additional extenders does not exceed about by weight of the total composition.

9. The composition of claim 8 wherein said additional extenders are selected from the group consisting of urea and glycerine.

References Cited UNITED STATES PATENTS 2,138,751 11/1938 Vohren. 2,399,456 4/ 1946 Yates et al. 3,044,974 7/ 1962 Tanabe et al. 2,179,607 4/ 1965 Suda et al. 3,219,613 11/1965 Keene. 3,222,306 12/1965 Suzumura et al.

WILLIAM H. SHORT, Primary Examiner E. NIELSEN, Assistant Examiner US. Cl. X.R.

ll7l39.5, 156, 161; 156-328 

38. THE EXTENDED RESIN SYSTEMS EXHIBIT COMPATIBILITY BOTH IN SOLUTION AND IN SOLID FORM AND FIND UTILITY AS FILM FORMERS, ADHESIVES, BINDERS AND SIZING COMPOSITIONS. 